Increased use of electronics and electrical devices on automobiles has increased the load on charging systems and driven a need for more efficient higher output alternators. A method used to increase the efficiency of the alternators is to liquid cool them rather than the traditional air-cooling. These liquid cooled alternators use the engine coolant, routed through the outer housing of the unit, to cool the electronics and allow more efficient internal geometry. Normally the alternator is bracket mounted to the front of the engine and the coolant is routed to the alternator via a flexible line secured by clamps. A second set of hoses and clamps then routes the coolant from the alternator back to the engine coolant system. 
Exhaust gas recirculation valves (EGR) also need to be liquid cooled to improve their performance and extend their usable life. Traditionally engine coolant is passed through an EGR valve mounting block or pedestal. The EGR is an emissions control device that admits exhaust gas into the inlet air of the engine. This exhaust gas is allowed into the intake air during certain engine operating conditions and is used to  control the tail pipe emissions of the engine. The high temperature of the exhaust gas, that the valve controls, drives the need for valve cooling. 
A coolant crossover, traditionally used on a V style internal combustion engine, carries the engine coolant from one bank of the engine to the opposite bank as part of the engine coolant circuit. This coolant crossover is commonly part of the intake manifold, or can be a separate stand-alone part, and frequently contains the housing for the coolant thermostat and provisions to mount the coolant temperature-sending unit. 